Saturday, December 19, 2015

Side Extension: Ground Works Week 1

As a reminder, we're in the process of building a single storey side extension off our house.  We had the garage demolished, and this week the ground works started.

When we first started talking about getting an extension, Niall sent me a link to a blog called Ten Square Metres.  Being a novice to building works in the UK, I found it fascinating.  It gave me some insight into what would be required.  In that build, a lot of it was DIY and took maybe a couple of years.  It gave me the idea that perhaps I could dig the foundations for our house myself.  

I honestly thought if I just dug a few hours a day, I could save us some ££.  But then I dug a 1 metre cubed hole (as a trial pit) for the structural engineer and decided that we'd pay for someone else to do the digging.  (It was hard!)   This is a photo of the trial hole, at a depth of about 83 cm.

The trial pit showed that the original house foundations were about a metre down, which meant the new foundations needed to be even deeper.  The ground works crew showed up on Tuesday and spent most of the day digging by hand to uncover the water and drain pipes.  On Wednesday, I spoke with Building Control, the builders and the structural engineer and they decided on a plan of action.  (Dig a new trench, divert the pipe and put in an access hatch.)

With the pipe unearthed, the rest of the foundation work went a lot faster.  The guys got most of the foundations dug on Wednesday and finished on Thursday.  JCB's make work go such much faster!

One thing I continue to miscalculate is the amount (and cost of removing) of unwanted debris.  

There was so much soil that it would have taken two regular skips (dumpsters) that fit in our drive or a large one, that would not have fit on our drive.   A street permit can take up to a week from Glasgow Council, so the soil piled up in our drive and then a truck with a grabber hauled it all away.

And we were left with a moat around the side of our house.

The guys filled it in with Level 1 Hardcore.  (This will be a bit of a photo dump.  Glasgow Council is understaffed at the best of times, but given its almost Christmas and they had a technical mishap this week, there was no chance of getting an inspector, so we'll be relying on photographic evidence if required when it comes time for getting the building certificate.)

And then they put in the steel to reinforce the concrete.

After the New Year, they'll come back and dig out the new runs for the pipes, so for now the section with the pipework is not getting filled in with concrete and aggregate until later.

Today (Friday) the premixed concrete showed up.  The guys wheeled it and poured it into the foundations.  It was a source of entertainment!

The guys were so fast with their wheelbarrows.  There were three running back and forth (I assume they didn't shoot it in due to distance or cost?)  Pretty soon the concrete was up to the right level.

So now the foundations are poured, they're 'covered' and they going to cure over the next two weeks, until after the holidays.

My understanding is the Ground Works team will come in and dig the new run for the pipework and the bricklayer is going to come in and build up brickwork to ground level.